WO1997011459A1

WO1997011459A1 - Method of exposing optical disk original, exposure apparatus therefor, and optical disk

Info

Publication number: WO1997011459A1
Application number: PCT/JP1996/002694
Authority: WO
Inventors: Kenji Igarashi
Original assignee: Kabushiki Kaisha Toshiba
Priority date: 1995-09-19
Filing date: 1996-09-19
Publication date: 1997-03-27
Also published as: JP4129294B2; EP0852378A4; US6203968B1; EP0852378A1

Abstract

When helical or concentric pit lines (p) are formed on an optical disk original (3) by irradiating a laser beam to the original (3), the laser beam is applied along path which is in parallel with, or diagonally to, the bit lines (p). For example, the laser beam is applied in such a manner as to describe an arcuate path which is in touch with the innermost pit line {p (point B)} and the outermost pit line {p (point A)} in the optical disk original (3), and uses as its diameter the sum of the radius r of the innermost pit line and the radius R of the outermost pit line.

Description

Patent application title: Optical disc master disc exposure method and exposure apparatus, and optical disc technical field

The present invention relates to an optical disk master exposure method and an exposure apparatus for forming a spiral or concentric pit row by irradiating an optical disk master with exposure light such as a laser beam or EB (electron beam). The present invention also relates to an optical disc duplicated using an optical disc master exposure method or an optical disc master produced by the exposure apparatus. Background art

The outline of optical disk production is as follows. First, a photo resist, which is a photosensitive material, is applied to a glass original plate, and this is used as an optical disk master.

Next, the photo resist of the master optical disc is exposed by a laser beam or EB, and the information to be recorded is processed into a concave shape, and this is processed into a pit signal (pit row). Record as

After that, processing such as development of the optical disk master is performed, and then reports are taken from the optical disk master, and the gold necessary for duplicating the optical disk is used as the master. Create a squatter.

The metal stamper is used for duplication to complete the final product, an optical disc.

In the manufacture of such optical disks, the optical disk master / P96 / 0 694

Two

Information is not recorded by exposing the laser beam to the resist 0

FIG. 24 is a configuration diagram of such an optical disc master recording apparatus. On stage 2 connected to spindle motor 1, optical disk master 3 is arranged. The optical disc master 3 is obtained by applying a photo resist, which is a photosensitive material, on a glass base plate.

On the other hand, a uniaxial slider 4 is arranged above the stage 2, and an optical head for exposure (exposure laser head) 5 is attached to a moving end thereof. The exposure optical head 5 irradiates the laser beam output from the exposure optical system 6 onto the optical disk master 3.

The uniaxial slider 4 has a movable end on which the exposure optical head 5 is mounted, which can be moved in the radial direction of the optical disk master 3, that is, a linear guide drive system.

The computer 7 controls the rotation of the spindle 1 and controls the movement of the single-axis slider 4 and also controls the laser beam output of the exposure optical system 6.

With such a configuration, the optical disc master 3 is rotated by the rotation of the spindle motor 1, and in this state, the exposure optical head 5 is moved in the − axial direction, ie, the optical disc master by the uniaxial slider 4. Slide in 3 radial direction.

As shown in Fig. 25, the optical head for exposure 5 slides linearly from the position of the outermost recording radius R on the optical disc master 3 to the position of the innermost recording radius r for recording. Do Near guide method). At this time, the sequence of the digital signals to be recorded and the slide movement direction are orthogonal.

As a result, the laser beam emitted from the exposure optical head 5 is irradiated onto the optical disc master 3 coated with a rotating resist. At this time, the irradiation of the laser beam is performed according to the information. When controlled, information groups such as pits and groups are recorded on the optical disc master 3.

At this time, the position of the exposure optical head 5 is measured by the laser interferometer 4a, and is always under feedback control by a fine movement system (not shown). Therefore, the resolution of the track pick-up by such an exposure apparatus is uniquely determined by the measurement resolution of the laser interferometer 4a.

Further, in such a driving system in which the exposure optical head 5 is linearly scanned, the uniaxial slider 4 and the like must have high rigidity. Therefore, the uniaxial slider 4 is, for example, a two-guide system. This means that the slider is used.

For this reason, such a slider has a configuration in which the optical disk master 3 is straddled, and the entire device becomes heavy and large.

On the other hand, as the driving method of the exposure optical head 5, in addition to the linear guide method in which scanning is performed linearly, a swing arm method found in magnetic recording methods of HDDs (hard disk drives) is used. Some have been applied.

In the driving by the swing arm method, as shown in FIG. 25, the exposure optical head 5 moves in an arc from the position of the outermost recording radius R to the position of the innermost recording radius r. . P

Four

In such a method, since the center of rotation of the swing arm is located outside the optical disc master 3, the drive trajectory of the exposure optical head 5 has a curvature, but it is almost similar to the linear guide method. Driving locus.

The position of such a swing arm type exposure optical head is ascertained by an encoder provided on a rotating shaft that drives the center of rotation of a driving trajectory. Therefore, the limit of the track pitch resolution in the swing-arm method is also determined by the resolution of this encoder.

When recording more information on an optical disc than it is now, it is difficult to increase the amount of information besides reducing the width of adjacent ぅ pit rows. The distance between adjacent rows of pits is becoming shorter than the length of one pit.

In order to perform such high-density recording, it is necessary to perform positioning in the radial direction with high accuracy when forming each pit.

In the current exposure equipment, the movement error when moving the exposure optical head directly appears as track pitch unevenness, so this movement error must be minimized as much as possible. No.

One way to meet this demand is to increase the resolution of the position detector used in the exposure apparatus.However, the position resolution of encoders and laser interferometers is stagnant. Due to the high cost, there is a strong demand for a high-resolution exposure apparatus that does not depend on the resolution of such a position detector. In each of the above driving methods, the position of the exposure optical head 5 or the table (or slider) on which the optical head is mounted is controlled using a linear encoder or a laser interferometer. The object whose position is to be controlled in essence is the focused spot of the laser beam for actually exposing and recording the resist, and the direct observation and measurement of the focused spot position is not performed. .

In the conventional linear guide-swing arm drive, a feed error occurs depending on the resolution of the position detector used, which leads to uneven track pitch. Difficult to do.

Accordingly, an object of the present invention is to provide an optical disk master exposure method and an exposure apparatus that can perform high-density recording on an optical disk master with a simpler or less expensive configuration.

Another object of the present invention is to provide an optical disc duplicated by using an optical disc master for high-density recording. Disclosure of the invention

According to a first aspect of the present invention, there is provided an optical disc master disc exposure method for irradiating an optical disc master with exposure light to form a spiral or concentric pit row on the optical disc master. Irradiation is a trajectory parallel or oblique to the pit row.

Further, the second invention provides an optical disk master exposure method for irradiating an exposure light to an optical disk master to form a spiral or concentric pit row on the optical disk master. Irradiation of the exposure light is performed so that the trajectory is in contact with at least one point in the pit row. D

In a third aspect of the present invention, in the second aspect of the invention, the irradiation of the exposure light is performed in such a manner that the exposure light is in contact with the innermost pit row on the optical disc master.

Further, according to a fourth aspect of the present invention, in the third aspect of the invention, the irradiation of the exposure light forms a linear trajectory.

In a fifth aspect of the present invention based on the second aspect, the irradiation of the exposure light is a locus in contact with the outermost pit row on the optical disk master.

In a sixth aspect of the present invention based on the third or fifth aspect, the irradiation of the exposure light is a locus of an arc.

In a seventh aspect of the present invention based on the second aspect, the irradiation of the exposure light is a trajectory in contact with an innermost pit row and an outermost pit row on the optical disk master.

In an eighth aspect of the present invention based on the second aspect of the present invention, in the second aspect of the invention, the irradiation of the exposure light is performed by setting the diameter to the sum of the radius of the innermost pit row and the radius of the outermost pit row on the optical disc master This is performed using the arc trajectory.

A ninth aspect of the present invention relates to an optical disk master exposure method for irradiating an optical disk master with exposure light to form a spiral or concentric pit array on the optical disk master. ,

The center point of the trajectory of the exposure light that forms an arc is within the optical disk master

A tenth aspect of the present invention provides a light source that irradiates an optical disc master with an exposure light to form a spiral or concentric pit row and outputs exposure light. A first rotating mechanism for rotating the optical disk master;

The optical disc master and the first rotating mechanism are integrally swung, and a second rotating mechanism is provided in which a rotation axis is disposed on a line passing through the optical disc master.

The eleventh invention is directed to an optical disc master exposure apparatus which irradiates exposure light to an optical disc master to form a spiral or concentric bit array on the optical disc master.

A light source for emitting exposure light,

A table on which the optical disk master is placed,

A front mirror that is at least vertically movable on an axis perpendicular to the center of the optical disc master and receives the exposure light from the light source, and receives the exposure light from the front mirror and receives the light from the front mirror. A frustum-shaped exposure mirror that irradiates the master disk,

There is provided irradiation control means for relatively rotating the front mirror and the optical disk master to control the trajectory of the exposure light.

In a twelfth aspect based on the eleventh aspect described above, the front-end mirror advances and retreats in the optical axis direction with respect to the first mirror fixed to the light source having a curvature and the light source, respectively. A second mirror is provided so as to be able to be provided, and the first mirror and the second mirror form a beam spot on the optical disc master.

According to a thirteenth invention, in the above-mentioned first invention, the curvature of one or both of the first mirror and the second mirror is controlled, and the lens action on the mirror surface is controlled. Is corrected. A fourteenth invention is the invention according to the above-mentioned first invention, wherein the first and second mirrors are opposite to the notch side of the notch hinge. The curvature of the mirror surface is controlled by controlling the voltage applied to the piezoelectric element provided between the notches of the notch hinge.

Also, in the fifteenth invention, the exposure light emitted from the optical head for exposure is irradiated on the master optical disc to form a spiral or concentric pit row on the master optical disc. Optical disc master exposure device

XY stage with optical head for exposure,

A drive control unit that drives the XY stage and scans the exposure optical head XY with respect to the optical disk master to make the trajectory of exposure light parallel or oblique to the pit row. And Further, a sixteenth invention is directed to an optical disc master exposure apparatus for irradiating exposure light to an optical disc master to form a spiral or concentric pit row on the optical disc master.

An exposure light projecting means for projecting the exposure light in a direction perpendicular to the optical disk master;

A front mirror that reflects the exposure light from the exposure light projecting means, and a half of the total distance of the outermost recording radius and the innermost recording radius of the optical disc master with respect to this front mirror. An exposure mirror which is arranged at an interval of 1 and irradiates the exposure light reflected by the front mirror perpendicularly to the optical disk master surface;

The front mirror is rotated relative to the optical disk master in a direction perpendicular to the optical disk master, and in response to this, the exposure mirror is spaced apart from the front mirror and the front mirror is maintained. And an arc moving means for relatively moving in an arc shape. Further, in the seventeenth invention, the exposure light emitted from the optical head for exposure is irradiated on the master optical disc to form a spiral or concentric pit row on the master optical disc. Optical disc master exposure device

A rotation mechanism that rotates the optical disc master at a predetermined speed, and the innermost circumference recording with the optical head for exposure inscribed on the outermost circumference recording radius of the pit row formed on the optical disc master Arc moving means for moving on an arc circumscribing the radius.

Also, in the eighteenth aspect of the present invention, the trajectory of the exposure light to the optical disc master is parallel or oblique to the spiral or concentric pit row to be formed on the optical disc master. This is an optical disk duplicated using an optical disk master produced by irradiating so that BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing a first embodiment of an optical disk master exposure method according to the present invention;

Fig. 2 shows the locus of the exposure light on the track by the same exposure method;

Fig. 3 shows the angle crossing the track pitch with respect to the scanning angle;

Fig. 4 shows the scan angle;

Fig. 5 shows a comparison of the sensitivity of the prior art to the scanning angle;

FIG. 6 is a diagram showing a modification of the trajectory of the exposure light; FIG. 7 is a diagram showing a modification of the trajectory of the exposure light; FIG. 8 is a configuration diagram showing a second embodiment of the optical disk master exposure apparatus according to the present invention;

FIG. 9 is a block diagram showing a third embodiment of the optical disk master exposure apparatus according to the present invention;

FIG. 10 is a block diagram showing a fourth embodiment of the optical disc master exposure apparatus according to the present invention;

Fig. 11 shows the narrowing of the laser beam spot by a toroidal mirror;

FIG. 12 is a block diagram showing a fifth embodiment of the optical disc master exposure apparatus according to the present invention;

Fig. 13A shows the specific configuration of the mirror with correction;

Fig. 13B is a specific configuration diagram with the piezoelectric element group of the mirror with correction;

FIG. 14 is a configuration diagram showing a sixth embodiment of the optical disk master exposure apparatus according to the present invention, viewed from above;

Fig. 15 is a side view of the optical disk master exposure system;

FIG. 16 is a configuration diagram showing a seventh embodiment of the optical disk master exposure apparatus according to the present invention;

FIG. 17 is a configuration diagram showing an eighth embodiment of the optical disc master exposure apparatus according to the present invention;

FIG. 18 is a block diagram showing a ninth embodiment of the turntable of the optical disk master exposure apparatus according to the present invention;

Fig. 19 is an external view showing the arrangement of the image sensor; Figure 20 is a diagram showing the light receiving action of the image sensor;

FIG. 21 is a block diagram showing a tenth embodiment of the suction mechanism of the optical disk master exposure apparatus according to the present invention;

Fig. 22 shows the shape of the groove on the suction surface of the turntable. Fig. 23 shows the shape of the groove on the suction surface of the turntable. Fig. 24 shows the configuration of a conventional optical disc master exposure system. The figure shows the driving trajectory of the conventional optical head for exposure; the best mode for carrying out the invention

(1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

In the method of exposing an optical disc master according to the present invention, as shown in FIG. 1, exposure light, for example, a laser beam is applied to the optical disc master 3, and a spiral or concentric pick-up is formed on the optical disc master 3. In the case of forming the array P, the laser beam irradiation is performed so as to follow a trajectory parallel or oblique to the array p (drive trajectory F of the optical head for exposure).

It is preferable that the trajectory of the laser beam irradiation be at least at one point of the pit system p, for example, the trajectory shown in FIG.

That is, the laser beam irradiation may be performed so that the locus may be in contact with the innermost pit row p on the optical disc master 3 at the point B.

The irradiation of the laser beam is performed so as to have a locus tangent to the outermost pit row p on the optical disc master 3 at the point A. You can use it.

The irradiation of the optical disk master 3 with this laser beam is performed so as to follow the locus of an arc centered at the point S.

The trajectory of the laser beam, which is the trajectory of the arc, is the radius of the innermost pit row p (the innermost recording radius) r and the radius of the outermost pit row p in the optical disc master 3 ( The diameter (R + r) of the sum of the outermost recording radius (R) and the center point S of the trajectory of the laser beam of the parenthesis exists in the plane of the optical disc master 3.

Therefore, in the optical disc master exposure method according to the first embodiment of the present invention, the optical disc master 3 is rotated at a predetermined speed, and the exposing optical head is moved to the outermost periphery of the optical disc master 3. The laser beam is inscribed in the recording radius R, circumscribes the innermost recording radius r, and is moved on the drive locus F whose diameter is (R + r), and the laser beam is directed to the optical disc master 3. Irradiation forms a pit row and records information.

If the driving locus F of the optical head for exposure is such that, for example, the outermost recording radius R is 60 mm and the innermost recording radius r is 20 mm, the length of the driving locus is 1 25.6 mm.

Here, the length of the driving trajectory according to the conventional rear guide system shown in FIG. 25 is 40 mm. The length of the driving trajectory F of the present invention is approximately 40 mm in the swing arm system. 3.14 times longer than each method.

Therefore, when the encoder and distance measuring device used in the conventional device are used as they are, the direction of the track (the direction of the pit row) is As a result, a resolution of 3.14 times (reduced error to 13.14) was obtained, realizing high resolution for information recording on the optical disc master 3 and high density recording. it can.

In addition, in the case of an optical disk duplicated using such an optical disk master 3, information is recorded at a high density. In actual disks, the actual resolution will be even greater, as the diameter will be 80 mm or 120 mm.

As shown in FIG. 2 (a), the trajectory F of the arc-shaped laser beam can be calculated by focusing on the nth track to the (n + 1) th track on the optical disk master 3, for example. Since they intersect at an angle with respect to the track direction, the length of the trajectory between these tracks is longer than that of the drive guide according to the rear guide method shown in FIG.

As a result, in the case of the trajectory F of the arc-shaped laser beam, the sensitivity is reduced by 1 / cos (90 ° -α).

FIG. 3 shows the relationship between the track pitch of the trajectory F and the intersecting angle α with respect to the scanning angle 0 (= 0 ° to 180 °) of the trajectory F of the arc-shaped laser beam shown in FIG. Here, the angle α at which the scanning angle Θ (= 120 °) intersects is 30 °.

Therefore, the intersection angle α becomes a convex curve with a curve value of = 30 °, and accordingly, the distance between the tracks of the trajectory F of the laser beam becomes longer, for example, the feed system Even if uneven feeding occurs, the effect on this can be reduced.

Fig. 5 is a diagram comparing the sensitivity of the arc laser beam trajectory F with the sensitivity of the conventional technology (linear guide method). The sensitivity by the trajectory F of the arc-shaped laser beam when the sensitivity of the conventional technology is set to “1” is shown.

That is, even when the scanning angle is 0 (= 120 °), the sensitivity due to the laser beam trajectory F is twice the sensitivity of the conventional technology, and before and after the scanning angle Q (= 120 °). It turns out that it is higher than the sensitivity.

Therefore, according to the present invention, it is possible to realize high resolution at the time of information recording on the optical disk master 3 and perform high density recording.

When exposure and recording on the optical disc master 3 are completed in this way, processing such as development on the optical disc master 3 is performed, and then information is copied from the optical disc master 3. Using this as a master, the metal stamper required to duplicate an optical disc is created.

The metal stamper is used for duplication, and the final product, an optical disc, is completed.

As described above, according to the first embodiment, the irradiation of the laser beam is defined as the sum of the radius r of the innermost pit row and the radius R of the outermost pit row on the optical disk master 3. The information is recorded with a high track density because there is no track pitch unevenness.

In addition, an optical disk duplicated using such an optical disk master 3 records high-density information that could not be realized conventionally.

Also, since the center S of the arc that is the trajectory of the laser beam is arranged inside the optical disk master 3, the laser beam is The length of the swing arm to be moved in an arc shape can be shortened, and the vertical deflection when irradiating a laser beam can be reduced. This is optimal for high-density information recording on the optical disc master 3.

The longer the distance from the support point that supports them to the exposure optical head, whether it is the linear guide or the swing arm, the greater the applied vibration is to the exposure optical head. This will cause position fluctuation.

Since this fluctuation is a rotational movement, it is a factor that changes the size of the exposure light spot, and at the same time, gives an error in the track pitch direction.

When the support point is outside the disc, there is always a certain distance between the support point and the exposure optical head, but the support point must be placed inside the disc. Thus, the exposure method of the present embodiment can be used, and errors due to the rotation can be reduced.

The present invention is not limited to the optical disk master exposure method of the first embodiment, but may be a laser beam trajectory as follows.

For example, as shown in FIG. 6, the irradiation of the laser beam may be in contact with the innermost pit row on the optical disk master 3 and may have linear trajectories Fa and Fb. . The trajectory Fb is in contact with the innermost pit row at right angles to the direction from the center.

At this time, it is possible to use a conventional linear guide type mecha- nism and achieve high-density recording. The trajectory of the irradiation of the laser beam only needs to be in contact with at least one point in the pit row p, and may be, for example, an arc that is in contact at point A or C as shown in FIG. Even in this case, recording can be performed with a resolution close to that of the first embodiment.

Further, as shown in the figure, the present invention can also be realized by a spiral trajectory contacting at points A and D, a spiral or a concentric circle as close as possible to the bit string p, and an ellipse or a free curve. You can achieve your goals.

(2) Next, a second embodiment of the present invention will be described.

FIG. 8 is a configuration diagram of an optical disc master exposure apparatus to which the above-described optical disc master exposure method is applied.

The surface plate 10 for suppressing vibration is provided with a first motor 11 as a first rotating mechanism. A turntable 12 is connected to the rotation shaft of the first motor 11, and the second rotation shaft 11 a on the turntable 12 is removed via a fixing member 13 when the rotation shaft 11 a is disengaged. A second motor 14 is provided as a rotating mechanism of the motor.

A turntable 15 is connected to the rotating shaft of the second module 14, and the optical disc master 3 is mounted on the turntable 15.

Since the second motor 14 for rotating the optical disk master 3 in this manner is provided at a position shifted from the rotation axis of the first motor 11, the rotation of the first motor 11 is performed. The axis 11a is arranged on a line passing through the optical disk master 3. That is, the rotating shaft 11 a of the first motor 11 is located on the drive locus F shown in FIG. It will be consistent with the heart s.

Further, a balancer 19 a having the same weight as the second motor 14 is provided at a position symmetrical with respect to the rotation axis 11 a of the second motor 14.

A lens mount 19b is provided on the optical path of the laser beam, and an imaging lens 19c is mounted on the lens mount 19b.

On the surface plate 10, a laser oscillator 17 is provided as an exposure light source via a support arm 16. A mirror 18 is arranged on the optical path of the laser beam output from the laser oscillator 17, and reflects the laser beam toward the optical disk master 3.

Next, the operation of the device configured as described above will be described. In the production of an optical disc, first, a photo resist, which is a photosensitive material, is applied to a glass substrate, and this is designated as an optical disk master 3.

Next, the optical disc master 3 is exposed by a laser beam, the information to be recorded is processed into a concave shape, and this is recorded as a pit signal.

That is, exposure and recording on the optical disc master 3 are performed as follows.

The optical disc master 3 is placed on a table 15 and rotated at a predetermined speed by driving a second motor 14.

At the same time, the first motor 11 rotates at a higher speed than the speed of the second motor 14.

On the other hand, when the laser beam is output from the laser oscillator 17, This laser beam is reflected by the mirror 18 and is emitted toward the optical disk master 3.

As a result, the laser beam comes into contact with the locus F shown in FIG. 1 above on the optical disc master 3, that is, at the point B with the innermost pit row P on the optical disc master 3, and Irradiation is made so that it touches the outermost pit row p at the point A and forms a trajectory of an arc with the center S.

After the exposure and recording on the optical disc master 3 are completed in this way, processing such as development on the optical disc master 3 is performed, and then information is copied from the optical disc master 3 The metal stamper required for duplicating the optical disc is created using this as a master.

As described above, according to the second embodiment, the irradiation of the exposure light is performed so as to be in a trajectory parallel or oblique to the pit row p, so that there is no track pitch unevenness. Information can be recorded at high density, and if the optical disc is duplicated using the optical disc master 3 of the parentheses, the information is recorded at high density.

In addition, since the center S of the arc, which is the trajectory of the exposure light, is arranged inside the optical disc master 3, the vibration when irradiating the exposure light can be reduced and the optical disc master can be reduced. It is most suitable for recording high-density information on 3.

(3) Next, a third embodiment of the present invention will be described.

Figure 9 shows an optical disk to which the above optical disk master exposure method was applied. FIG. 2 is a configuration diagram of a master exposure apparatus.

The base plate 20 has a two-layer structure on which a base plate 22 is provided via a support 21.

The turntable 23 is provided on the surface plate 20, and the optical disc master 3 is placed on the turntable 23.

On the base plate 22, a laser oscillator 24 is provided as an exposure light source for the optical disc master 3. The laser oscillator 24 outputs a laser beam in the same direction as the surface direction of the optical disk master 3. On the optical path of the laser beam, an optical system 24a for focusing the laser beam on the three optical disk masters is arranged.

Also, the first mirror as a front-end mirror is provided on the base plate 22 with a strength of 25. The first mirror 25 passes along the optical path of the laser beam output from the laser oscillator 24, passes through the center of the optical disk master 3, and faces the surface of the optical disk master 3. It is located on the vertical line.

The first mirror 25 is arranged so as to be a reflection surface at an angle of 45 ° with respect to the surface of the optical disk master 3, and transmits the laser beam output from the laser oscillator 24. However, the light falls on the optical disk master 3 in a direction perpendicular to the surface thereof toward the center position of the optical disk master 3.

A mirror elevating mechanism 26 is provided in the direction in which the first mirror 25 emits the laser beam.

The mirror raising / lowering mechanism 26 holds the second mirror 27 as a front-end mirror, and transfers the second mirror 27 to the optical disk. 2 Q

A guide body 28 for vertically moving with respect to the surface of the master 3 and an elevating motor (not shown) for elevating and lowering the second mirror 27 along the guide body 28 are provided.

The mirror raising / lowering mechanism 26 includes a rotary motor 29 having a second mirror 27 attached to a rotary shaft. The rotating motor 29 rotates the second mirror 27 around a rotation axis perpendicular to the surface of the optical disk master 3. The rotary motor 29 is moved up and down integrally with the second mirror 27 by driving the elevating motor.

The mirror elevating mechanism 26 drives the elevating motor and the rotating motor 29 in synchronization with each other. By driving the elevating motor and the rotating motor 29, the second mirror 27 For example, it descends while rotating from top to bottom.

The second mirror 27 is arranged so as to form a reflecting surface at an angle of 45 ° with respect to the optical path of the laser beam reflected from the first mirror 25, and converts the laser beam into the optical disk master 3. The light is reflected in a direction parallel to the surface direction.

On the lower surface of the base plate 22, a truncated conical mirror 30 is provided as a third mirror.

The conical mirror 30 extends from a predetermined position on a vertical line passing through the center position of the optical disk master 3 to a mirror at an angle of 45 ° to the surface of the optical disk master 3. Are arranged.

The conical mirror 30 reflects the laser beam from the second mirror 27 and irradiates the laser beam perpendicular to the surface of the optical disk master 3. It is connected with.

The rotation control unit 30a has a function of controlling the rotation of the mirror lifting mechanism 26 and the rotation motor 29, and in particular, traces the trajectory of the laser beam irradiating the surface of the optical disc master 3, for example, As shown in Fig. 1, the locus of the arc that touches the innermost pit row p on the optical disc master 3 at the point B, touches the outermost pit row P at the point A, and has the center S It has a function to control the rotation of the mirror elevating mechanism 26 and the rotating motor 29 so that the light is irradiated so that

Alternatively, in the case of exposing the optical disc master to a fixed state without rotating it, the mirror elevating mechanism draws the trajectory of the laser beam concentrically or spirally along the desired pit row. It has a function of interlocking control of the rotary motor 29 and the rotary motor 29.

Next, the operation of the device configured as described above will be described. The optical disc master 3 is placed on a turntable 23. On the other hand, when the laser beam is output from the laser oscillator 24, the laser beam is reflected by the first mirror 25 and is emitted toward the center of the optical disk master 3.

Further, the laser beam is reflected by the second mirror 27 in the direction of 45 °, travels to the conical mirror 30, and is reflected by the second mirror 27 in the direction of 45 °. The light is reflected and illuminates the surface of the optical disc master 3 in the vertical direction.

At this time, the rotation of the mirror elevating mechanism 26 and the rotation motor 29 is controlled by the rotation control unit 30a, so that the second mirror is controlled. The trajectory of the laser beam, which is reflected by the conical mirror 30 and irradiates the surface of the optical disk master 3, is the innermost row of pits on the optical disk master 3 as shown in Fig. 1 above. It touches p at point B, and touches the outermost pit row p at point A, and forms an arc locus centered on S.

When the exposure and recording of the optical disc master 3 are completed in this way, the optical disc master 3 is thereafter duplicated using the optical disc master 3 to complete the optical disc as a final product as described above. I do. On the other hand, such an apparatus can perform the following exposure and recording. The optical disc master 3 is placed on a fixed table 23.

On the other hand, when a laser beam is output from the laser oscillator 24, the laser beam is reflected by the first mirror 25 and is emitted toward the center position of the optical disk master 3.

Further, the laser beam is reflected by the second mirror 27 in the direction of 45 °, travels to the cone-shaped mirror 30, and is reflected by the mirror 30 in the direction of 45 °. The light is reflected to the surface of the optical disk master 3 in a direction perpendicular to the surface.

At this time, the second mirror 27 rotates at a constant speed around the vertical line passing through the center position of the optical disk master 3 by the driving of the rotary motor 29, and at the same time, the optical disk As seen from the surface of the disc master 3, it descends at a predetermined speed from above to below.

Therefore, the laser beam reflected by the second mirror 27 and further reflected by the conical mirror 30 and irradiated onto the optical disk master 3 is formed by the optical disk shown in FIG. For the entire area from the position of the innermost recording radius r of the master 3 to the position of the outermost recording radius R, 3 6 0. Is scanned over the entire circumference.

When the exposure and recording on the optical disc master 3 are completed in this way, thereafter, the optical disc master 3 is used for duplication as described above, and the final product optical disc is produced. Complete.

As described above, in the third embodiment, the second mirror 27 is rotated and moved by controlling the rotation of the mirror elevating mechanism 26 and the rotary motor 29, and the irradiation of the laser beam is stopped. Since the trajectory is formed so as to be parallel or oblique to the system, there is no unevenness in track pitch, information can be recorded at high density, and this optical disc master 3 is used. If the optical disk is duplicated by using this method, information will be recorded at a high density.

In addition, the first and second mirrors 25, 27 and the conical mirror 30 are arranged, and the second mirror 27 is rotated up and down while rotating. As a result, it is possible to reduce the weight of the driving part and to eliminate the need to rotate the optical disc master 3, thereby making it possible to use an optical disc master such as when a spindle motor is used. Asynchronous deflection due to the displacement of the center of gravity between the spindle motor and the spindle motor can be eliminated, and the centering mechanism between the master optical disc 3 and the spindle motor can be eliminated. In addition, since the center S of the arc, which is the trajectory of the exposure light, is arranged inside the optical disc master 3, the path of the exposure light can be shortened, and the vibration when the exposure light is irradiated is reduced. It is suitable for high-density information recording on the optical disk master 3.

Therefore, the optical disk master 3 on which the exposure and recording processes have been performed has no track pitch unevenness, and information is recorded at a high density. An optical disk duplicated using such an optical disk master 3 has a high density of recorded information.

(4) Next, a fourth embodiment of the present invention will be described. The same parts as those in FIG. 9 are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 10 is a configuration diagram of an optical disk master exposure apparatus to which the above optical disk master exposure method is applied.

As a first mirror, a concave first toroidal mirror 31 is arranged. Each of the first toroidal mirrors 31 is formed on a mirror surface having a predetermined curvature, and narrows the short radius side.

In addition, a concave second toroidal mirror 32 is arranged as the second mirror. The first door mirror 32 is formed on one side of the mirror having a predetermined curvature, and narrows the short radius side.

These first and second toroidal mirrors 31 and 32 narrow the laser beam spot of the laser beam output from the laser oscillator 24 as shown in FIG. Thus, the optical disk master 3 is illuminated.

In such a description, the light and recording on the optical disk 3 are performed as follows:

The optical disk 3 is pirated on a rotating table 23 and rotated at a predetermined speed.

When a laser beam is output from the laser oscillator 24, the laser beam is reflected by the first toroidal mirror 3]. The light falls toward the center of the disk master 3 and then reflects at the second toroidal mirror 32 at an angle of 45 °, and further at the cone mirror 30 at an angle of 45 °. The light is reflected and irradiated in the direction perpendicular to the surface of the optical disk master 3.

At this time, the second toroidal mirror 32 and the conical mirror 30 are controlled by controlling the rotation of the mirror lifting mechanism 26 and the rotation motor 29 by the rotation control unit 30a. The trajectory of the laser beam reflected on the optical disk master 3 and irradiating the surface of the optical disk master 3 contacts the innermost pit row p of the optical disk master 3 at point B as shown in FIG. The trajectory of the arc that touches the outer pit row p at the point A and has the center S.

The laser beams reflected by the first and second toroidal mirrors 31 and 32 are respectively focused on the laser beam spots as shown in Fig. 11 and applied to the surface of the optical disc master 3. Is done.

When the exposure and recording of the optical disc master 3 are completed in this way, thereafter, the duplication is performed using the optical disc master 3 as described above, and an optical disc as a final product is completed. .

—However, such a device can perform the following light and recording. The optical disc master 3 is placed on a turntable 23. In this case, the turntable 23 is fixed without rotating.

When a laser beam is output from the laser oscillator 24, this laser beam is reflected by the first toroidal mirror 31 and falls down toward the center of the optical disk master 3, and then the second beam Reflected in the direction of an angle of 45 ° by a toroidal mirror 32, and a circle 2 6

The light is reflected by the conical mirror 30 in the direction of the angle 45 and radiated in the direction perpendicular to the surface of the optical disc master 3.

At this time, the second toroidal mirror 32 rotates at a constant speed around a vertical line passing through the center position of the optical disk master 3 by driving the rotary motor 29, and at the same time, the optical disk The master 3 descends at a predetermined speed from above to below when viewed from the surface of the master 3. Thus, the trajectory of the laser beam is drawn concentrically or spirally over the entire surface of the disc.

Therefore, the laser beam applied to the optical disc and the disc 3 is shifted 360 ° from the entire area of the optical disc master 3 from the position of the innermost recording radius r to the position of the outermost recording radius R. Scanning is performed all around.

At this time, the laser beams reflected by the first and second toroidal mirrors 31 and 32 are respectively focused on the laser beam spots and irradiated onto the surface of the optical disk master 3. As described above, in the fourth embodiment, the first and second toroidal mirrors 31 and 32 are formed on one surface of a mirror having a predetermined curvature, respectively. Since the spots are narrowed down to irradiate the surface of the optical disc master 3, in addition to the effects similar to the effects of the third embodiment described above, information is recorded on the optical disc master 3. Higher density ₀

An optical disk duplicated using such an optical disk master 3 records information at a high density.

(5) Next, a fifth embodiment of the present invention will be described. In addition, The same parts as those in FIG. 9 are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 12 is a configuration diagram of an optical disk master exposure apparatus to which the above optical disk master exposure method is applied.

A first mirror with correction 33 is arranged as a first mirror. The first mirror with correction 33 is configured so that the curvature of the mirror surface can be changed and controlled to correct the lens action on the mirror surface.

In addition, a second mirror with correction 34 is arranged as a second mirror. This second mirror with correction 34 is configured to be capable of changing and controlling the curvature of one surface of the mirror in the same manner as the first mirror with correction 33 so as to correct the lens effect on one surface of the mirror. It is what you do.

These first and second mirrors with correction 33, 3 and 4 have mirror surfaces 33a and 33 on the back of notched hinge 35 as shown in the external view of Fig. 13 (a). 4a, and two piezoelectric element groups 36, 37 are provided between the notch ends at different intervals on the notch side as shown in FIG. Note that each of the piezoelectric element groups 36 and 37 has a single layer of piezoelectric exciters of the same number.

On the other hand, the curved surface control unit 38 controls each applied voltage to each of the pressure-element groups 36 and 37, and the first or second mirror with correction. It has the function of controlling the curvature of one or both mirror surfaces and correcting the lens action on the mirror surfaces. PT JP / 69

2 8

In other words, the curved surface control unit 38 has a table of applied voltages to the piezoelectric element groups 36 and 37 corresponding to the elevation position of the second mirror with correction 34, and has a table. It has a function of reading out an applied voltage corresponding to the elevation position of the mirror 34 with the second correction and applying the voltage to each of the piezoelectric element groups 36 and 37.

With such a configuration, exposure and recording on the optical disc master 3 are performed as follows.

The optical disk master 3 is placed on a turntable 23 and rotated at a predetermined speed.

When a laser beam is output from the laser oscillator 24, the laser beam is reflected by the first mirror 33 with correction and is incident on the center of the optical disk master 3.

After reading, the laser beam is reflected by the second corrected mirror 34 at an angle of 45 °, and is further reflected by the conical mirror 30 at 45 ° and is reflected by the optical disk master. Irradiated vertically to surface 3 o

At this time, since the mirror elevating machine drawing 26 and the rotating motor 29 are rotationally controlled by the rotation control unit 30a, the mirror 34 with the correction of 2 and the circle The trajectory of the laser beam reflected by the Iwami mirror 30 and radiated to the ίϊϊί of the optical disk 3 is, as shown in FIG. At the same time, it touches the point sequence 1) at the point B and ¾ the point ¾ to the outer pitch line p at the point Λ.

Further, the first and second corrected mirrors 33 and 34 are controlled by the stern control 38 to the first or second pressure Ui element groups 36 and 37. The applied voltage is controlled, and the radius of curvature on the minor radius side of each of the mirror surfaces 33a and 34a is controlled.

That is, the radii of curvature of the first and second mirrors with correction 33 and 34 are set according to the elevation position of the second mirror with correction 34 and these mirrors with correction 33 Correct the lens action of 3,4. Therefore, the laser beam applied to the optical disk master 3 is optimally set to have a focusing property on the optical disk master 3.

When the exposure and recording on the optical disk master 3 are completed in this way, the optical disk master 3 is then duplicated using the optical disk master 3 as described above, and the final product is obtained. The optical disk is completed. On the other hand, such an apparatus can perform the following exposure and recording. The optical disk master 3 is placed on a rotary table 23. In this case, the rotating mirror 23 is fixed without rotating.

When the laser beam is output from the laser oscillator 24, the laser beam is reflected by the perforated mirror 33 of ί¾ · 1 and radiated toward the central position of the optical disk master 3 ίΐΐ. Is done.

The laser beam is illuminated by the iili

The light is reflected in the direction of 5 °, is further radiated by the circular mirror 30 in the direction of 45 °, and irradiates the "of the optical disk 3 in the direction of“ "”. At this time, the second li-correction mirror 34 receives the optical disk 3 at the center of the optical disk 3 due to the rotation of the motor 29, and sets the line to the rotation. And rotates at a constant speed, and when viewed from the perspective of the optical disk element 3, descends at a predetermined speed from top to bottom. Therefore, the laser beam applied to the optical disk master 3 is 360 ° in the entire region from the position of the innermost recording radius r of the optical disk master 3 to the position of the outermost recording radius R. It is scanned around the circumference.

Here, similarly to the above, the first and second mirrors with correction 33 and 34 are supplied with a voltage applied to the first or second piezoelectric element group 36 and 37 by the curved surface control unit 38. The radius of curvature on the minor radius side of each mirror surface 33a, 34a is controlled.

That is, the radii of curvature of the first and second corrected mirrors 33 and 34 are set in accordance with the ascending and descending positions of the second corrected mirrors 34 and 34. 3 Correct the lens action of 4.

Therefore, the laser beam applied to the optical disk master 3 is set to have an optimal light-collecting characteristic on the optical disk master 3.

As described above, in the fifth embodiment, the first and second mirrors with correction 33, 34 are controlled to have predetermined curvatures, respectively. In addition to achieving the same effects, the light-collecting characteristics for the optical disk master 3 can be set optimally, and the density of information recorded on the optical disk master 3 can be further increased.

In addition, in the case of an optical disk duplicated using such an optical disk master 3, information is recorded at a high density. (6) Next, a sixth embodiment of the present invention will be described.

FIGS. 14 and 15 are configuration diagrams of an optical disk master exposure apparatus to which the above-described optical disk master exposure method is applied, wherein FIG. 14 is a configuration diagram viewed from above, and FIG. 15 is a side view. FIG. 丄

The master disk suction disk 40 vacuum-adsorbs and fixes the optical disk master 3 placed on the upper surface.

An XY drive mechanism 41 is provided above the master disk suction plate 40. That is, the two X-axis guides 42 and 43 are arranged in parallel with each other at an interval longer than the diameter of the optical disc master 3. These X-axis guides 42 and 43 are provided with X-axis sliders 44 and 45 movably, respectively.

Two Y-axis guides 46 and 47 are provided between the X-axis sliders 44 and 45 in parallel with each other.

Note that the X-axis guides 42 and 43 and the Y-axis guides 46 and 47 are perpendicular to each other.

An XY stage 48 is movably provided on each of the Y-axis guides 46 and 47. The XY stage 48 is provided with an optical head 49 for exposure.

The exposure optical head 49 has a focus actuator on the objective lens, so that the focusing spot is always the just focus on the optical disc master 3. I'm wearing

The optical system for guiding the laser beam to the exposure optical head 49 is as follows.

Laser oscillator 50 is arranged to output a laser beam in the X に direction. A 45 ° mirror 51 is arranged on the X-axis slider 45 on the optical path of the laser beam output from the laser oscillator 50.

The 45 ° mirror 51 reflects the laser beam output from the laser oscillator 50 in the Y-axis direction. On the XY stage 48 on the optical path of the reflected laser beam, a 45 ° mirror 52 for epi-illumination is arranged.

The 45 ° mirror 52 for the epi-illumination emits the laser beam toward the optical head 49 for exposure.

On the other hand, the drive control unit 53 issues drive control signals to the X-axis sliders 44, 45 and the Υ stage 48, and drives the Υ stage 48 by controlling the Υ coordinates to expose the optics for exposure. The head 49 is scanned above the optical disk master 3 and, for example, the trajectory of the laser beam applied to the surface of the optical disk master 3 is moved to the innermost side of the optical disk master 3 as shown in FIG. It has a function of contacting the pit row ρ at the point と共に and tangent to the outermost pit row ρ at the point 駆動, and has the function of controlling the drive so as to form an arc locus with the center S.

Next, the operation of the device configured as described above will be described. In the production of an optical disc, first, a photo resist, which is a photosensitive material, is applied to a glass base plate, and this is referred to as an optical disc master 3.

The drive control unit 53 converts the position of each recording pit to be recorded on the optical disc master 3 into XY coordinates, and moves the XY stage 48 according to the XY coordinates. The XY stage 48 is moved by the X-axis guides 42 and 43 and the Υ-axis guides 46 and 47 which are driven according to the drive control signal, whereby the exposure optical head 49 is moved. Are continuously positioned above the optical disc master 3 on which each recording pit is to be recorded. Or, feed control is performed continuously.

That is, when the optical disc master is being rotated, the exposure optical head 49 is at a point Β with respect to the innermost pit row における of the optical disc master 3 as shown in FIG. Positioning or feed control is performed so that the laser beam is in contact with the outermost pit row ρ at the point Α and along the trajectory of the circular arc laser beam having the center S.

When the exposure optical head 49 is positioned corresponding to each recording position, a laser beam is output from the laser oscillator 50.

This laser beam is reflected in the Y-axis direction by a 45 ° mirror 51, and then falls toward an exposure optical head 49 by a 45 ° mirror 52.

The optical head 49 for exposure irradiates the focused spot of the laser beam on the optical disc master 3 with just focus.

Accordingly, the exposure optical head 49 is positioned above all the recording pits of the optical disk master 3 to be recorded by the movement of the XY stage 48, so that the optical disk master 3 Information is recorded over the entire circumference.

—On the other hand, optical disk master 3 is placed on the fixed table. In this case, the XY stage 48 is moved so that the trajectory of the laser beam is drawn concentrically or spirally along the desired pit row. Alternatively, exposure can be performed by a method of raster-scanning the entire surface of the master from one side to the opposite side.

When the exposure and recording of the optical disk master 3 are completed in this way, after that, information is taken from the optical disk master 3 and this is used as a master for the optical disk. The necessary metal stampers are created for the duplication.

As described above, in the sixth embodiment, the exposure optical head 49 is positioned and managed in the XY coordinates, and is continuously positioned or controlled, so that the second embodiment is performed. As with the effect of the form, information can be recorded on the optical disk master 3 at a high density. If the optical disk is replicated using such an optical disk master 3, high density The information is recorded in the.

(7) Next, a seventh embodiment of the present invention will be described.

FIG. 16 is a configuration diagram showing an optical disk master exposure apparatus to which the above optical disk master exposure method is applied.

The platen 60 is provided with a spindle motor 61 as a rotating mechanism. A turntable 62 is attached to the rotating shaft of the spindle motor 61.

The turntable 62 has a suction surface formed thereon, and vacuum-adsorbs and fixes the optical disc master 3 placed thereon. — On the upper side of the surface plate 60, a base plate 63 is provided. On an upper surface of the base plate 63, a laser oscillator 64 for outputting a laser beam as exposure light is provided.

A first mirror 65 is provided on the optical path of the laser beam output from the laser oscillator 64, and emits the laser beam in a direction perpendicular to the surface of the optical disk master 3. . Note that the first mirror 65 is arranged at an angle of 45 ° with respect to the laser beam optical path.

A hollow motor 66 is mounted on the lower surface of the base plate 63 with the laser beam path reflected by the first mirror 65 as a rotation axis.

The hollow motor 66 has a function as an arc moving means, and has a hollow portion 67 for passing the laser beam reflected by the first mirror 65, and has a circular shape. Part of the rotating body 68 rotates around the rotation axis. On the lower surface of the hollow motor 66, an optical head 69 for exposure is provided.

The exposure optical head 69 includes a second mirror 70, a third mirror 71, and an objective lens 72.

Of these, the second mirror 70 has a mirror surface arranged at an angle of 45 ° with respect to the surface of the optical disk master 3, and the laser reflected by the first mirror 65. The beam is reflected in the direction horizontal to the disc.

The third mirror 71 is different from the second mirror 70 by the difference between the outermost recording radius R and the innermost recording radius r of the optical disk master 3. They are spaced at half the total distance.

Further, the third mirror 71 has a mirror surface arranged at an angle of 45 ° with respect to the surface of the optical disc master 3, and the laser beam reflected by the second mirror 70 The beam falls on the optical disk master 3.

The objective lens 72 is disposed on the optical path of the reflected laser beam of the third mirror 71, has a focus function, and constantly adjusts the laser beam to the optical disk master 3. The light is illuminated on the optical disc master 3 as a focused light spot.

Here, when the hollow motor 66 rotates, in the exposure optical head 69, the second mirror 70 rotates about the rotation axis of the hollow motor 66, and together with this, the second mirror 70 rotates. The second mirror 71 and the objective lens 72 move together on an arc centered on the second mirror 70.

That is, as shown in FIG. 1 above, the objective lens 72 of the exposure optical head 69 is inscribed in the outermost peripheral recording radius R and is also circumscribed in the innermost peripheral recording radius r. Next, the operation of the device configured as described above will be described. In the production of optical discs, first, a photo resist, which is a photosensitive material, is applied to a glass base plate, and this is applied to the optical disc master.

3

Next, this optical disc master 3 is exposed by a laser beam, and the information to be recorded is processed into a concave shape. And record.

That is, exposure and recording on the optical disk master 3 are performed as follows.

When the spindle motor 61 rotates at a constant rotation speed, the turntable 62 rotates at a constant rotation speed in response to the rotation, and the optical disc master 3 fixed to the suction table also rotates at a constant rotation speed. It rotates at high speed.

On the other hand, when a laser beam is output from the laser oscillator 64, the laser beam falls on the first mirror 65 and passes through the hollow portion 67 of the hollow motor 66 to the exposure optics. Reach the second mirror 70 of the head 69.

Then, the laser beam is reflected by the second mirror 70 in a direction parallel to the disk master, and further reflected by the third mirror 71, and is reflected by the objective lens. At 72, the optical disk master 3 is irradiated as a just-focused spot.

-Out this Noto, hollow motor 6 6 given speed ^YI: in which drive rotation. Due to the rotation W] of the hollow motor 66, the second mirror 71 and the objective lens 72 are integrally moved around the second mirror 70 on an arc.

That is, 対物 the objective lens 72 of the Mitsukawa Optical Head 69 is inscribed in the outer periphery ¾ as shown in FIG. 21 and circumscribed in the ik inscribed m ψ ¾r as shown in FIG. · Ι Move along locus F. This ¾ Keigao F is a circle a with ft diameter of (R + r), for example.

In this way, the K light for the optical disk 3 is completed. Upon completion, the information is copied from the optical disc master 3 and the metal stamper necessary for duplicating the optical disc is created using this as the master.

As described above, according to the seventh embodiment, apparently high resolution (error reduced to 1Z3.14) in the track direction can be obtained, and the optical disc can be obtained. Higher resolution can be achieved when recording information on master 3, and high-density recording can be performed.

Also, since the center S of the arc which is the trajectory of the laser beam is arranged inside the optical disc master 3, the distance between the second mirror 70 and the third mirror 71 is shortened. This makes it possible to reduce vibration when irradiating a laser beam, and is optimal for recording high-density information on the optical disc master 3.

In addition, in the case of an optical disk duplicated using such an optical disk master 3, information is recorded at a high density. (8) Next, an eighth embodiment of the present invention will be described. The same parts as those in FIG. 16 are denoted by the same reference numerals, and detailed description thereof will be omitted.

Fig. 17 is a block diagram of an optical disc master exposure apparatus to which the optical disc master exposure method is applied.

On the surface plate 60, two base plates 80 and 81 are supported by support members 82 and 83 at predetermined intervals, respectively.

A laser oscillator 84 is provided on the upper base plate 80, and a laser beam output from the laser oscillator 84 is provided. oy

The first mirror 85 is arranged on the optical path.

A motor 86 is provided on the lower base plate 81, and an optical head 87 for exposure is connected to a rotating shaft of the motor 86.

The optical head for exposure 87 includes a second mirror 88, a third mirror 89, and an objective lens 90.

The second mirror 88 has an angle 45 between the mirror surface and the surface of the optical disc master 3. The laser beam reflected by the first mirror 85 is reflected in a direction parallel to the master disk.

The third mirror 89 has a distance of one half of the total distance between the outermost recording radius R and the innermost recording radius r of the optical disk master 3 with respect to the second mirror 88. G

The third mirror 89 has a mirror surface arranged at an angle of 45 ° with respect to the surface of the optical disc master 3, and the laser reflected by the second mirror 88. The beam falls on the optical disk master 3.

The objective lens 90 is arranged on the optical path of the reflected laser beam of the third mirror 89 and has a focus actuator, and always irradiates the laser beam to the optical disk master 3. It irradiates the optical disk master 3 as a focusing spot of the focus.

Here, when the motor 86 rotates, the second mirror 88 rotates around the rotation axis of the motor 86 in the exposure optical head 87, and the second mirror 88 rotates together with the second mirror 88. Mirror 8 8 and objective lens 9 0 7/1 45 4 Q

Move together on an arc centered on the second mirror 88.

That is, the objective lens 90 of the exposure optical head 87 has its drive locus F inscribed in the outermost recording radius R and circumscribed in the innermost recording radius r as shown in FIG. Go to 0

Next, the operation of the device configured as described above will be described. In optical disc manufacturing, when the spindle motor 61 rotates at a constant rotation speed, the evening table 62 rotates at a constant rotation speed in response to the rotation, and the optical disk fixed by suction is fixed to the table. Master disk 3 also rotates at a constant rotation speed.

On the other hand, when a laser beam is output from the laser oscillator 84, the laser beam is incident on the first mirror 85 and the second mirror of the optical head 87 for exposure is used. 8 Reach 8

Then, the laser beam is reflected at the second mirror 88 in the direction of an angle of 45 °, is further reflected by the third mirror 89, and is justified by the objective lens 90. The optical disk master 3 is irradiated as a focusing spot for focusing.

At this time, since the motor 86 is driven to rotate at a predetermined speed, the third mirror 89 and the objective lens 90 are integrally formed on an arc around the second mirror 88. Moving.

That is, the objective lens 90 of the exposure optical head 87 has a drive trajectory F inscribed in the outermost peripheral recording radius R and circumscribed in the innermost peripheral recording radius r as shown in FIG. Move according to the above. The driving trajectory F is an arc having a diameter of (R + r). When the exposure and recording on the optical disc master 3 are completed in this way, information is taken from the optical disc master 3 and the metal stamper required for duplicating the optical disc using the master as a master. Is created.

As described above, according to the eighth embodiment, similarly to the seventh embodiment, apparently high resolution (with an error of 13.14) in the track direction is obtained. ), And high-density recording can be performed on the optical disk master 3 by achieving higher resolution when recording information.

Also, since the center S of the arc which is the trajectory of the laser beam is arranged inside the optical disk master 3, the distance between the second mirror 88 and the third mirror 89 is shortened. This makes it possible to reduce the vibration when irradiating the laser beam, and is optimal for recording high-density information on the optical disk master 3.

In addition, in the case of an optical disk duplicated using such an optical disk master 3, information is recorded at a high density. The seventh and eighth embodiments may be modified as follows.

For example, in the seventh and eighth embodiments, the exposure optical heads 69 and 87 are rotated so that each of the objective lenses 72 and 90 is located at the outermost periphery as shown in FIG. While moving on the drive locus F inscribed in the recording radius R and circumscribed in the innermost recording radius r, the exposure optical heads 69, 87 are fixed, and the spindle is By rotating the motor 61, the trajectory of the laser beam on the optical disc master 3 may be the driving trajectory F shown in FIG. 1, and even with such a configuration, the seventh and eighth embodiments can be implemented. The same effect as in the embodiment can be obtained.

(9) Next, a ninth embodiment of the present invention will be described.

FIG. 18 is a diagram showing the surroundings of a turntable such as a rotary table 23 on which an optical disc master 3 used for an optical disc master exposure equipment is mounted. Here, a case where the present invention is applied to the seventh and eighth embodiments will be described.

A turntable 91 is connected to the rotating shaft of the spindle motor 61. The turntable 91 has a groove of the suction mechanism 92 for sucking the optical disc master 3 in an area smaller than the area within the innermost recording radius r of the optical disc master 3.

An image sensor 93 as an exposure light sensor is provided below the surface of the optical disk master 3 opposite to the surface irradiated with the laser beam.

This image sensor 93 has a plurality of light-receiving elements arranged in a row, and is formed in an arc shape corresponding to the drive locus F of the objective lenses of the exposure optical heads 69 and 87, for example, as shown in FIG. It has been.

The image sensor 93 receives a laser beam transmitted through the optical disc master 3 and outputs a light receiving signal corresponding to the light receiving position.

The feedback control section 94 is output from the image sensor 93. The received light receiving signal is input, and from this light receiving signal, the condensing spot position of the laser beam applied to the optical disc master 3 is detected, and the difference between this condensing spot position and the spot setting position is detected. And a function of positioning the exposure optical heads 69 and 87 so as to eliminate this difference.

The feedback control unit 94 counts the reference clock when the exposure optical heads 69 and 87 are moving in accordance with the driving locus F, and counts this reference clock. The spot setting position corresponding to the default value is set in advance.

With such a configuration, the following operations are provided in addition to the operations of the seventh and eighth embodiments.

In other words, the suction mechanism 92 for sucking the optical disk master 3 sucks the optical disk master 3 in an area narrower than the area within the innermost recording radius r of the optical disk master 3, and Since a space is formed in the lower surface of the optical disk master 3 corresponding to the recording area of the disk master 3, the laser beam during exposure and recording on the optical disk master 3 transmits through the optical disk master 3. However, this does not reflect back to optical disc master 3 again.

Therefore, the exposure of the optical disc master 3 and the exposure at the time of recording can be completely avoided.

The laser beam transmitted through the optical disk master 3 enters the image sensor 93 with a divergent angle as shown in FIG.

The image sensor 93 receives a laser beam having a divergence angle transmitted through the optical disk master 3 by a plurality of light receiving elements, The light receiving signal corresponding to the light receiving position is output.

The feedback control unit 94 receives the received light signal output from the image sensor 93, compares the received light signal with a predetermined reference level a, and determines the reference level a. The intermediate position (2b / 2) of the received signal is estimated as the focused spot of the laser beam.

Then, the feedback control unit 94 finds the difference between the condensing spot position and the spot setting position, and sets the exposure optical heads 69 and 87 to eliminate this difference. Position.

Thus, according to the ninth embodiment, in addition to the effects of the seventh and eighth embodiments, uneven exposure of the optical disc master 3 can be avoided, and the optical head 6 for exposure can be used. By positioning 9, 87, the laser beam focusing spot can be controlled to a predetermined position, and the density of information recording can be further increased.

In addition, in the case of an optical disk duplicated using such an optical disk master 3, information is recorded at a high density. (10) Next, a tenth embodiment of the present invention will be described.

The tenth embodiment of the present invention is an optical disc master exposure method in which the method of adsorbing an optical disc master is improved.

This optical disc master exposure method includes a first step of setting the suction surface of the turntable to an atmospheric pressure state when the optical disc master 3 is placed on the turntable;

After the first step, a second step of applying a positive pressure between the adsorption surface of the turntable and the optical disk master 3;

After this second step, the suction surface of the turntable and the optical disc And a third step of reaching a predetermined vacuum state with a plurality of degrees of vacuum between the master 3 and

After this third step, the optical disc master 3 is irradiated with a laser beam to record information.

FIG. 21 is a configuration diagram of a suction mechanism of an optical disk master exposure apparatus to which the optical disk master suction method is applied.

The rotary table of the spindle motor 100 is connected to a rotary table 101, on which the optical disk 3 is sucked and fixed.

As shown in FIG. 22, the turntable 101 has a convex portion at the portion corresponding to the exposure area of the optical disc master 3 as shown in FIG. Thus, only the grooves (recesses) are formed.

This turntable 101 has two stages of electromagnetic air valves in series, ie, the first stage magnetic air valve (hereinafter referred to as the first magnetic air valve). 103, ^ 2nd-stage ^ magnetic air valve (hereinafter, referred to as a second 空気 magnetic air valve)] 04 is connected with the pipe interposed.

These '1 and 2nd Ί1Ϊ magnetic air valves] 0 3 and 1 04 are three valves □ R, Λ, and それ, respectively. if The column is connected. An empty pump]. 05 is connected to the R of the latter '2', the magnetic air valve〗 04 of the latter stage.

Also, the compressed air source〗 07 is connected to the valve port P of the air valve] .03 via ^]. The above-mentioned compressed air source 107 is connected to the valve port P of the second electromagnetic air valve 104 through a connector 108 with an electromagnetic valve and a second regulator 109. Are connected through piping.

However, the first electromagnetic air valve 103 is arranged such that the valve port A on the compressed air source 107 side or the second electromagnetic air valve 1 0 The valve port R on the 4 side is selected and switched.

In addition, the second electromagnetic air valve 104 is connected to the valve port P on the compressed air source 107 side or the vacuum pump 10 with respect to the valve port A on the suction surface side on the first electromagnetic air valve 103 side. The valve port R on the 5 side is selected and switched.

The pressure control device 110 controls the operation of the first and second electromagnetic air valves 103, 104, and the ejector with solenoid valve 108, and enlarges the suction surface of the turntable 101. Atmospheric pressure is applied, and then a positive pressure is applied between the suction surface of the turntable 101 and the optical disc master 3.After that, the suction surface of the turntable 1 1 and the optical disc master 3 are connected. Between several degrees of vacuum, for example, (atmospheric pressure-100 OmmHg)-(atmospheric pressure-200 mmHg) low vacuum, then (atmospheric pressure-700 mmHg) or less It has a function to reach a high degree of vacuum.

Next, the operation of the device configured as described above will be described for a case where the device is applied to a turn table in the optical disc master exposure apparatus of the seventh embodiment.

In the production of optical discs, first, a photo resist, which is a photosensitive material, is applied to a glass base plate, and this is applied to the optical disc master. 3

The optical disc master 3 is attracted and fixed to the turntable 101 (turntable 62 in the seventh embodiment).

That is, as a first step, the pressure control device 110 opens the first electromagnetic air valve 103 to the second electromagnetic air valve 104 side (the valve port A → R).

Then, the second solenoid valve 109 of the solenoid valve-equipped connector 108 is closed, and the supply of compressed air from the compressed air source 107 is cut off. At this time, the ejector 108 with the solenoid valve is open to the atmospheric pressure side.

Thus, the suction surface of the turntable 101 is formed in an atmospheric pressure state.

The optical disc master 3 is placed on the suction surface of the turntable 101 in this atmospheric pressure state.

In the second step, the optical disk master 3 is centered with respect to the turntable 101, that is, the center position of the optical disk master 3 with respect to the rotation center of the turntable 101 is set. When positioning, the pressure control device 110 opens the first electromagnetic air valve 103 to the side of the compressed air source 107 (valve port P). The electromagnetic valve-equipped connector 108 may be in any state.

By opening the valve port P of the first electromagnetic air valve 103, the compressed air from the compressed air source 107 is supplied to the first electromagnetic valve 106, the first electromagnetic air valve 1 It is supplied to the suction surface of the turntable 101 through 03. At this time, the turntable 101 is attracted. Three

The compressed air supplied to the surface is supplied irrespective of the state of the other equipment.

The supply pressure of the compressed air supplied to the turntable 101 is regulated by the first regulator 106, for example, at most +1 kgf with respect to the atmospheric pressure. The pressure is set slightly positive at about / cm ² .

As a result, a positive pressure (positive pressure) is set between the optical disc master 3 and the turntable 101.

However, in a state of positive pressure between the optical disk master 3 and the turntable 101, the optical disk master 3 is centered by the centering mechanism with respect to the turntable 101. .

Thereafter, in the third step, the pressure control device 110 opens the first electromagnetic air valve 103 to the second electromagnetic air valve 104 side (the valve port A → R), and Open the solenoid air valve 104 of 2 to the connector 108 side with solenoid valve (valve port A → P).

Then, the compressed air from the compressed air source 107 is supplied to the solenoid valve-equipped ejector 108 through the second regulator 109 to form a vacuum state.

At this time, the supply pressure to the solenoid valve-equipped ejector 108 is regulated by the second regulator 109, and the positional deviation during the suction after the centering is reduced. In order to prevent this, the ultimate vacuum degree of the ejector with solenoid valve 108 is set to a low vacuum degree, for example, (atmospheric pressure—100 mm Hg) to (atmospheric pressure—200 mm Hg).

As a result, the optical disk master 3 is adsorbed to the turntable 101 by the low degree of vacuum, so-called light absorption. O

Next, the pressure control device 110 opens the first electromagnetic air valve 103 to the second electromagnetic air valve 104 side (valve port A → R), and the second electromagnetic air valve 10 Open 4 to the vacuum pump 105 side (valve port A → R). At this time, the solenoid valve-equipped connector 108 may be in any state.

As a result, the suction surface of the turntable 101 is sucked by the vacuum pump 105 through the first and second electromagnetic air valves 1.03, 104, and sucks and fixes the optical disk master 3. .

At this time, the attained vacuum on the suction surface of the turntable 101 is set to a high vacuum of, for example, (atmospheric pressure-700 mni Hg) or less.

When the optical disc master 3 is attached and fixed to the turntable 101 in this manner, in the case of the optical disc master exposure apparatus of the seventh embodiment, the spindle motor 61 rotates at a constant speed. The turntable 62 rotates at a constant rotation speed in response to this, and the optical disc master 3 adsorbed and fixed to the turntable 62 also rotates at a constant rotation speed.

On the other hand, when the laser beam is output from the laser oscillator 64, the laser beam is incident on the first mirror 65 and passes through the hollow portion 67 of the rotating hollow motor 66 to the exposure optics. Reach the second mirror 70 of the head 69.

Then, the laser beam is reflected by the second mirror 70, is further reflected by the third mirror 71, and is focused by the objective lens 72 on the just focus. To the optical disc master 3 It is.

At this time, since the hollow motor 66 is rotationally driven at a predetermined speed, the objective lens 72 of the exposure optical head 69 moves along the arc of the driving locus F shown in FIG. .

As a result, the optical disc master 3 is exposed to a laser beam, and the information to be recorded is processed into a concave shape, which is recorded as a pit signal.

At this point, the laser beam applied to the optical disk master 3 passes through the optical disk master 3 and reaches the turntable 101, and the suction surface of the turntable 101 is shown in Fig. 22. As shown in FIG. 23, only the protrusions or grooves (recesses) are formed in the portion corresponding to the exposure area of the optical disc master 3, so the influence of the reflected laser beam from the turntable 101. Exposure non-uniformity after receiving is reduced.

When exposure and recording on the optical disc master 3 are completed in this way, information is copied from the optical disc master 3 and the metal stamper required for duplicating the optical disc using the master as a master. Is created.

The metal stamper is used for duplication, and the final product, the optical disc, is completed.

As described above, in the tenth embodiment, when the optical disc master 3 is placed on the table 101, the suction surface of the turntable 101 is brought into the atmospheric pressure state, Next, a positive pressure is applied between the suction surface of the turntable 101 and the optical disc master 3, and then the suction surface of the turntable 101 and the optical disc master 3 are set. The optical disc master 3 is sucked and fixed at two levels of vacuum, a low vacuum and a high vacuum, between the vacuum and the vacuum, that is, to prevent imbalance in the vacuum state. Since the suction surface of the optical table 101 is gradually or continuously shifted from the atmospheric pressure to a high vacuum, the optical disc master 3 is pre-centered on the turntable 101 in advance to adsorb it. Even if it is fixed, the centering of the optical disc can be absorbed without shifting the centering.

Also, since the suction surface of the turntable 101 corresponding to the exposure area of the optical disc master 3 is formed only in the convex portion or the groove (concave portion), the reflected laser beam from the turntable 101 is formed. Exposure non-uniformity can be reduced under the influence of the above.

The tenth embodiment may be modified as follows.

For example, the supply pressure is not limited to using two vacuum generators, the vacuum pump 105 and the solenoid valve-equipped inductor 108, and the supply pressure is electrically controlled using one vacuum generator. The ultimate vacuum degree may be controlled by the conversion of electricity and air that can be converted, and the vacuum may be continuously increased to adsorb.

In addition to connecting the two-stage electromagnetic air valves in series, a plurality of electromagnetic air valves may be connected to adjust the ultimate vacuum in multiple stages.

Although the tenth embodiment has been described as applied to a turntable in the optical disk master exposure apparatus of the seventh embodiment, the optical disk of the eighth embodiment is described. It can be applied to the turntable of a master mask exposure system. Monkey

As described above, by using the optical disk master exposure method and the apparatus thereof according to the present invention, exposure with a resolution far exceeding the limit of the laser interferometer or encoder to be used can be performed regardless of the driving method. Therefore, it is possible to contribute to increasing the capacity of conventional optical discs.

In addition, the optical disc of the present invention provides high-quality recording with less error pits when the information in the optical disc is increased in density, because high-density recording can be performed with high accuracy. Becomes possible. Industrial applicability

As described above, the optical disc master disc exposure method and the exposure apparatus according to the present invention are useful technologies for producing master discs of not only CDZDVDs but also optical discs of higher recording density in the future. This is particularly suitable when it is desired to configure the device at low cost.

Further, the optical disc according to the present invention can provide a compact recording medium at a low cost with respect to an increase in the amount of information accompanying the development of multimedia culture in the future.

Claims

The scope of the claims

1. An optical disc master disc exposure method for irradiating an optical disc master with exposure light to form a spiral or concentric pit row on the optical disc master.

A method for exposing an optical disk master, wherein the irradiation of the exposure light is a locus parallel or oblique to the pit row.

2. An optical disk master exposure method for irradiating an optical disk master with exposure light to form a spiral or concentric pit row on the optical disk master.

A method for exposing an optical disc master, comprising: irradiating the exposure light so as to form a locus that contacts at least one point of the pit row.

3. The optical disk master exposure method according to claim 2, wherein the irradiation of the exposure light is performed such that the irradiation of the exposure light is in a locus in contact with the innermost pit row in the optical disk master. .

4. The method for exposing an optical disc master according to claim 3, wherein the irradiation of the exposure light is a linear locus.

5. The optical disc master exposure according to claim 2, wherein the irradiation of the exposure light is performed so as to be a trajectory contacting the outermost pit row on the optical disc master. Method.

6. The optical disk master exposure method according to claim 3, wherein the irradiation of the exposure light forms a locus of an arc.

7. A track for irradiating the exposure light with the innermost pit row and the outermost pit row on the optical disk master. 3. The method for exposing a master optical disc according to claim 2, wherein the method is performed so as to leave a mark.

8. Irradiation of the exposure light is performed by a locus of an arc having a diameter equal to a sum of a radius of the innermost pit row and a radius of the outermost pit row on the optical disc master. 3. The method for exposing an optical disc master according to claim 2, wherein:

9. An optical disk master exposure method for irradiating an optical disk master with exposure light to form a spiral or concentric pit row on the optical disk master;

An optical disc master exposure method, characterized in that a center point of the trajectory of the exposure light that forms the arc is within the optical disc master.

10. A light source that outputs exposure light to form a spiral or concentric pit row by irradiating the optical disc master with the light source.

A first rotation mechanism for rotating the optical disk master; and an optical disk master and the first rotation mechanism integrally swingingly moving, and a rotation axis passing through the optical disk master. A second rotating mechanism located on the line;

An optical disc master exposure apparatus, comprising:

11. An optical disc master exposure apparatus that irradiates exposure light to an optical disc master to form a spiral or concentric pit row on the optical disc master.

A light source for emitting the exposure light,

A table on which the optical disc master is placed;

At least a vertically movable axis is provided on an axis orthogonal to the center of the optical disk master, and the front disk receives exposure light from the light source. And

A frusto-conical exposure mirror that receives the exposure light from the front mirror and irradiates the optical disc master with the exposure light;

Irradiation control means for relatively rotating the front mirror and the optical disc master to control the trajectory of the exposure light;

An optical disc master exposure apparatus, comprising:

12. The front mirror includes a first mirror fixed to a light source having a curvature and a second mirror provided to be able to advance and retreat in the optical axis direction with respect to the light source. 12. The optical disk master exposure according to claim 11, wherein a beam spot is formed on the optical disk master by using the first mirror and the second mirror. apparatus.

13. The curvature of one or both of the first mirror and the second mirror is controlled to correct the lens action on the mirror surface. 13. The optical disc master exposure apparatus according to claim 12, wherein

14. The first and second mirrors are provided on the back of the notch hinge opposite to the notch side, and are applied to the piezoelectric element provided between the notches of the notch hinge. 13. The optical disk master exposure apparatus according to claim 12, wherein a curvature of a mirror surface is controlled by controlling a voltage.

15. Exposure light emitted from the optical head for exposure is irradiated onto the optical disk master to form a spiral or concentric pit row on the optical disk master. In the master disc exposure system, An XY stage on which the exposure optical head is mounted, and an XY stage driven by driving the XY stage to XY scan the exposure optical head with respect to the optical disk master to irradiate the exposure light with the irradiation light. A drive control unit for making a mark parallel or oblique to the pit row;

An optical disc master exposure apparatus, comprising:

16. An optical disc master exposure apparatus that irradiates exposure light onto an optical disc master to form a spiral or concentric pit row on the optical disc master.

Exposure light projection means for projecting the exposure light in a direction perpendicular to the optical disk master;

A front mirror that reflects the exposure light from the exposure light projecting means, and two minutes of the total distance of the outermost recording radius and the innermost recording radius of the optical disc master to the front mirror. An exposure mirror arranged at an interval of 1 and irradiating the exposure light reflected by the front mirror perpendicularly to the optical disk master surface;

The front mirror is relatively rotated about an axis perpendicular to the optical disk master, and the exposure mirror is moved in response to the rotation to adjust the distance between the front mirror and the front mirror. Arc moving means for maintaining and moving the front mirror relatively in an arc around the front mirror;

An optical disc master exposure apparatus, comprising:

17. An optical disc master that irradiates the exposure light emitted from the exposure optical head onto the optical disc master and forms a spiral or concentric pit row on the optical disc master. Exposure equipment hand,

A rotation mechanism for rotating the optical disc master at a predetermined speed; and an inscribed optical head for exposure at an outermost circumference recording radius of the pit row formed on the optical disc master. And an arc moving means for moving on an arc circumscribing the innermost recording radius.

18. An optical disk having an optical head that forms exposure light on the optical disk master, the exposure light being provided opposite to a turntable that rotates about the center of the optical disk master. In the master exposure system,

An optical disc master exposure apparatus, comprising: a feed mechanism for moving the optical head in a direction other than the center of the optical disc master.

19. Irradiation such that the trajectory of irradiation of the exposure light onto the optical disk master is parallel or oblique to the spiral or concentric pit row to be formed on the optical disk master. An optical disc characterized by being duplicated using an optical disc master produced in this way.